The Brexit vote in the UK referendum could result in some London-based banks being forced to relocate their workforces to Paris and Frankfurt, Jonathan Hill, the EU’s financial services commissioner has told German business newspaper Handelsblatt.

With uncertainty growing over the future status of EU expats working in the UK, Mr Hill warned that the vote to leave the EU would have a severe impact on the UK’s financial and banking sector. “I’ve visited London, Manchester and other British financial centres in the past weeks and warned of the consequences of an exit from the EU,” he said.

“Then it could happen that banks and investment funds shift activities and jobs to Frankfurt and Paris.”

US investment bank JP Morgan has described a Brexit as a “terrible deal” for the British economy and warned it could cut up to 4,000 jobs in the UK. Several other banks have talked of relocating and even HSBC, when deciding to retain its international HQ in London earlier this year, said it might have to move hundreds of jobs to Paris if there were a Brexit vote.

Much, of course, will depend on the deal the UK hammers out with the remaining EU, including access to continental financial markets. In March, rating agency Standard & Poor’s warned that international banks could refocus their European businesses away from Britain, particularly if the UK was no longer part of the passporting arrangement, which allows credit institutions from EU countries to carry out their business in another member state without having to obtain an official authorisation from the relevant regulator.

“A vote to leave would result in complex, prolonged negotiations with the EU over the terms of the UK’s exit, with considerable uncertainty over the outcome,” said S&P.